on the Marine Barometer . 257 
the low state of the mercury, continued until we got without 
side of Groote Eyland. 
3d. On the east side of Groote Eyland, and the west side 
of the gulph, northward from that island, we sometimes had 
sea and land breezes with fine weather ; we had also two 
moderate gales of wind from the eastward, of from two to 
four days continuance each, with one of which there were 
heavy squalls of wind and rain ; sometimes also, the winds 
were tolerably steady between north and west, with fine 
weather. During all these variations, the mercury never dif- 
fered much from its average standard 29,90 ; and it seemed 
as if the increase of density in the air, from the wind blowing 
upon the coast, was equal to its diminution of quantity from 
the fall of rain and strength of the wind ; and on the other 
side, that the wind from over that corner of Arnhem's Land 
permitted the mercury to descend, as much as the fine 
weather would otherwise have occasioned it to rise. 
Upon the north side of Groote Eyland, the mercury stood 
higher than usual for five days, and during this time the wind 
blew with more regularity from NW, the only exception 
being for a few hours in the afternoons, when it commonly 
sprung up from the NE in the manner of a sea breeze : the 
weather remained fine during these five days, and the height 
of the mercury averaged 29,94. 
4th. In the neighbourhood of Cape Arnhem, the mercury 
usually stood about 29,90, whether the wind was from NW, 
NE, or east, if the weather was fine ; but if by chance the 
wind shifted to the south side of west, off the land, it de- 
scended to 29,80 though the weather remained the same ; and 
this was its standard during those times when strong gusts 
Lla 
